While affluent consumers with mild hearing loss can readily obtain professionally fitted binaural hearing aids for a high cost, that high cost is out of the question for the 20-40% of those who may need hearing aids but cannot afford them. FIG. 1 illustrates an exemplary high-cost custom-made hearing aid 10 that provides good performance during constant use. The conventional in-the-ear hearing aid 10 may comprise a battery drawer 14, which swings out to accept a battery (not shown). The battery must be oriented properly before insertion to prevent wedging the battery in backwards or causing damage to the hearing aid. Microphone inlet 12 and volume control 16 are standard features on such hearing aids. Ear-tip 18 is custom molded to fit an individual's ear, so that the hearing aid must be oriented properly for insertion in the ear in order to avoid discomfort and obtain a good seal to the ear. When properly oriented and inserted, the snug fit of the ear-tip in the ear canal provides a good seal and prevents uncomfortable feedback of sounds.
Low-cost mail-ordered or over-the-counter hearing aids (such as “Hunter's aids” at sporting-goods stores) are available for a low cost compared to the professionally fitted binaural hearing aids. However, these lower cost hearing aids have certain disadvantages. For example, some of the low-cost hearing aids utilize ear-tips that fit only a fraction of the population, causing feedback whistling or discomfort for many of those who try them. Other low-cost hearing aids utilize ear-tips that may seal well if the correct one of multiple sizes is chosen, but are not cleanable and thus must be replaced regularly. Most of these low-cost hearing aids have high distortion and generally poor sound quality. Additionally, most low-cost hearing aids lack automatic wide-dynamic-range-compression amplification such as that found in the high-quality hearing aids designed for constant use, automatically adjusting the gain and frequency response so that quiet sounds are made audible while loud sounds are not uncomfortably amplified.
FIG. 2A illustrates an exemplary low-cost hearing aid 20 available on the market. This hearing aid 20 has an advanced volume control. However, an uncomfortable feedback noise typically sets in before adequate gain is obtained, rendering this type of hearing aid of marginal or no benefit to the user. In this hearing aid 20, the battery may be replaced by unscrewing battery cap 24 and inserting a new battery. For the hearing aid 20 to function, proper battery orientation must be maintained. Hearing aid 20 must be properly oriented to fit in the ear. Single-flange ear-tip 28 provides a seal to some ears, but internal feedback on many of these hearing aids results in a whistling noise at low volume control settings, which makes the seal to the ear irrelevant. The hearing aid 20 also comprises microphone inlet 22 and volume control 26. This hearing aid is not designed to an individual's ear, but is instead intended to fit most users.
FIG. 2B illustrates another exemplary low-cost hearing aid 25 for people with mild to moderate hearing loss, available for purchase in non-medical environments. Hearing aid 25 may be worn as required, and not necessarily all the time. This hearing aid can be fitted at the time of purchase using a system such as, for example, Microsound's Eartuner interactive fitting system. This hearing aid is also not designed to an individual's ear, but is instead intended to fit most users. Hearing aid 20 must be properly oriented to fit in the ear.
FIG. 3 illustrates another exemplary low-cost hearing aid 30, intended to fit most users. The hearing aid 30 is a sophisticated one-size-fits most hearing aid. This hearing aid may contain high-quality amplification. Hearing aid 30 may comprise a microphone inlet 32, a battery drawer 34, and volume control 36. Ear-tip 38 has been statistically chosen to provide comfortable fit to a large number of persons when properly oriented in the ear. In this design, only low-gain amplification is usually possible because of a lack of custom fit of the ear-tip to the ear, which results in a lack of complete seal. As with the custom hearing aid 10 of FIG. 1, the battery in hearing aid 30 must be properly oriented before insertion to prevent wedging the battery in backwards, which may result in damaging the hearing aid. Hearing aid 30 must also be properly oriented to fit properly in the ear canal. Variations on hearing aid 30 are now available in which a choice of several foam ear-tips may be snapped onto a molded tip of ear-tip 38. When the proper size is chosen, hearing aid 30 can provide a good seal and good comfort for the user. Such foam ear-tips must be replaced at regular intervals, the battery must be properly oriented, and the hearing aid must still be properly oriented to fit in the ear.
Existing hearing aids are designed in irregular shapes that may approximate the shape of the ear, but are difficult for many purchasers to insert because the hearing aid must be orientated properly to be inserted comfortably and to work properly. Furthermore, existing hearing aids have battery drawers that may be difficult for certain persons to manipulate, and that require the battery to be inserted with the proper polarity, which may be a daunting task for persons whose vision and possibly sense of feel have been impaired with age or illness.
Another prior art alternative may be the Songbird disposable hearing aid, which is a low-cost hearing aid and has at least a few of the problems discussed hereinabove. The Songbird hearing aid has been compared favorably with a well-known high-performance two-channel analog hearing aid and two well-known digital hearing aids. However, the problem with the Songbird hearing aid is that because it is disposable, the annual cost of purchasing a pair of aids each month is substantially less than the cost of most professionally-dispensed hearing aids, but still out of reach of many persons in lower-income brackets.
Simplified, mass-produced, in-the-canal hearing aids currently exist (U.S. Pat. No. 4,870,688, filed May 27, 1986) and may be produced in large quantities to fit most hearing aid users, thus eliminating a need for production of hearing aids produced to fit only the one individual's ear. There are at least several disadvantages associated with this device. For example, even though the hearing aids are mass-produced, thus requiring no need for producing an individualized fit for each patient and possibly lowering the cost of production and the cost of the device, the components are selected by the patient to fit their individual hearing needs. This requires the patient to visit a specialist, which may possible increase the over-all cost of getting the hearing aid device. In addition, the design of the hearing aid shell is such that it only fits in the ear canal if oriented in a certain direction.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.